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Re:TSMC Kicks Off Volume Production of 7nm Chips by CamperBob2 on Tuesday April 24, 2018 @11:58PM (#16918536)
So, what does determine the "marketing" nomenclature for a given process node, if not a specific feature size or wavelength?

I find it impossible to believe that some obscure semiconductor industry people get together in a hidden smoke-and-particulate-matter-free room, come up with a completely-random number, and name their process after it.

Re:TSMC Kicks Off Volume Production of 7nm Chips by kurthr on Wednesday April 25, 2018 @01:15AM (#16918782)
It's worse than that... there's not jist an industry group (ITRS), there's also the foundries making it up themselves. They're buying similar equipment and selling similar transistor densities (except for Intel which has finer geometries and higher densities for a given node), but few are directly compatible on density, clock-rate, or power consumption after 28nm.

https://en.m.wikipedia.org/wiki/International_Technology_Roa...

Scalling really started falling apart in the late 90s around .25u, and then (incidentally) about the time CPU MHZ stopped scaling... by 65nm both gate and transistor length got wonky. Then after 28nm they moved to fin-FETs and multi-patterning making comparisons even more difficult.

https://semiengineering.com/a-node-by-any-other-name/

Re:TSMC Kicks Off Volume Production of 7nm Chips by awalton on Wednesday April 25, 2018 @02:13AM (#16918963)
It used to be a specific feature size: the length of the gate. But, even as the wheels came off of that pretty quickly, the convention stayed pretty simple and familiar: each process node halves the size of the one before it - you can print double the number of transistors at the smaller process node. To make the math work out, that means each process node "name" is sqrt(1/2) ~= 0.7x smaller than the last, which gives you the easy-to-follow node names from 3um to about 3nm (when people tend to switch to ångströms or picometers since it moves the decimal kindly).

Even as things got sticky due to advancements in transistor construction meaning that old metrics like gate length were obsolete, we were still roughly following the trend laid out ahead of us for decades. A new process would double your density, letting you roughly cut the size of your old chip in half.

...Until a few fab companies just up and decided "You know what, fuck it, we can't actually catch up to Intel, but if what if we just... say that we did?" (...and I wish I was kidding. Take a look: https://m.eet.com/images/eetimes/2013/10/1319679/20-Value.jp... vs https://m.eet.com/images/eetimes/2013/10/1319679/16-Value.jp...).

So pretty quickly, TSMC decided that they'd just advance the node table, despite not actually increasing the density by double as you'd expect. "Next generation" 20nm processes became "16nm" and "14nm" on marketing docs, despite the process capabilities not changing that much (or even at all in some cases), with the only thing close to a justification given is that "FinFETs are different. They perform better than planar FETs so we should be able to give them a new node name." GloFo and Samsung quickly took the bit and followed their lead as they began FinFET manufacturing.

And apparently since nobody blinked an eye or set off alarm bells about these fabs basically lying about their capabilities, they got away with it and are now continuing the trend downwards. "10nm" processes from TSMC, Samsung and GloFo measure up to Intel's 14nm, and now "7nm" processes measure up to Intel's 10nm. It's actually pretty surprising Intel hasn't thrown up its hands and joined them on the fun, or even come up with their own marketing spin on it yet. "Intel's new 7nm-xtreme manufacturing process (actually it's just 10nm+)" or whatever.

Re:TSMC Kicks Off Volume Production of 7nm Chips by kingosticks on Wednesday April 25, 2018 @05:26AM (#16919856)
Who exactly would be responding to these alarm bells?

If I'm making a chip I want to use the node that best fits my product. Might not even be the latest one. But if they offer me 2x the memory destiny, 1.6x the logic density all at the same/lower power - I'll take it! Sure, the tracks are huge and I need a huge tall stack-up but that's not really my problem. I really don't care what marketing speak they use to refer to it. I have zero interest how long the gate is, I care about what chip I can make with this.

And Intel can do what they want. Their fab offering is very uncompetitive.

Re:TSMC Kicks Off Volume Production of 7nm Chips by Valmar on Wednesday April 25, 2018 @07:49AM (#16920627)
Intel's nm numbers are also pure marketing, I believe.